Failing including <allegro.h>

[Thomas Kipp]

I'm using the IDE DevC++[Version:5.8.2]
I'm creating a simple Win32-Console-Project
I try to integrate the Haeaderfile <allegro.h>
I was downloading the package "Allegro-4.2-1aved.DevPak", succesfully
Iwas integrating this package by using the tool "Package Manager/Install/"Allegro-4.2-1aved.DevPak",succesfully
I was intergrating the object "liballeg.a" by using the menuponit "Project/Project Options/Parameter/Linker", followed by using the tool C:\Dev-Cpp\lib\liballeg.a to add to, successfully!
I try to start following sourcecode;

include <allegro.h>

int main(){
int x=0,y=0;

allegro_init();
install_keyboard();
set_color_depth(16);
set_gfx_mode( GFX_AUTODETECT, 800 , 600, 0, 0);

while(key[KEY_ESC]==0)
{
   textprintf_ex(screen, font, x, y, makecol(255, 255, 255), makecol(0, 0, 0), "Hello world!");
}

return 0;

}
END_OF_MAIN();

,,,withe following error message:

[Error] allegro.h. No such file or directory compilation terminated
recipe for target 'main1.o' failed

If I try to use the headerfile <stdio.h> in order to get the sentence "Hello world" at the screen, everything is all right. But I want to use the graphic opportunities through integrating the headerfile <allegro.h>.
Unfortunately, that's not possible, 'cause of upper error message.

Thx a lot in advance for each way to solve this surely simple problem!!

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